It is important in candle magic to use a fresh candle for every spell, and to allow the candle to burn itself out.
Before using spell candles in magic, they need to be cleared of all energies they have picked up along the way to you. This is a simple operation, but very neccessary.
Take the spell candle you are going to use and place it on the altar, place a small bowl of either spring water, rose water or lavender water next to the candle. Dampen your hand with the water and run your damp hand over every part of the candle.
It is best to recite a blessing such as: I cleanse this candle of all negative energies and make it pure. Accept my blessings for the work ahead. Or something of your choice. If using more than one candle, repeat the process on all of them. They are now ready for you to inscribe.